Do not share, sync or export bookmarks if you bookmared Quick Access URL to your Counterwallet

Do not use TOR or proxies that cannot be trusted.

Never import other private keys known to other people (e.g. if someone asks you to "help" them by importing their private key to your wallet) to your Counterwallet.

Remember that private keys imported to Counterwallet cannot be recovered from the pass phrase (because unlike "native" addresses generated by Counterwallet they cannot be unlocked by your pass phrase), so do not discard private keys of imported addresses if those addresses need to be recoverable from outside of Counterwallet.